FR3125996A1 - Actuator for actuating at least one movable member of a vehicle transmission - Google Patents

Abstract

The present invention proposes an actuator (1, 1') for actuating at least one movable member of a vehicle transmission, said actuator (1, 1') comprising a housing (6) in which a motor is housed electric (2) having a shaft (21) on which is mounted a first pinion (22, 22'), a toothed wheel (3, 3') having teeth (31, 31') meshing with the pinion (22, 22 ') and a torque output element (33) capable of being coupled with the transmission, characterized in that the housing (6) comprises a pin (80) projecting in the direction of the toothed wheel (3, 3') and to the right of the first gable (22, 22'). Figure for abstract: Figure 7

Description

Actuator for actuating at least one movable member of a vehicle transmission

The invention relates to an actuator for actuating at least one movable member of a vehicle transmission, in particular a vehicle having at least two wheels, for example a bicycle also called a bicycle or a tricycle also called a tricycle.

The invention finds its application in particular in the field of actuators for changing gear ratios of a transmission or gear box associated with the vehicle. Such a gear transmission or gearbox is for example described in document WO 2012/156613 A1. However, many other applications are possible.

Such an actuator finds its usefulness by being coupled to the transmission or gear box of the vehicle. The vehicle may be electrically assisted, that is to say it comprises an electric drive motor coupled to the transmission of said vehicle. The vehicle can also be conventional, that is to say without electric assistance.

There is a need to change the ratios of the transmission of the vehicle automatically so that the transmission operates in its optimum operating range without causing significant effort on the part of the user and/or the drive motor. The actuator according to the invention thus simplifies the use of the vehicle for the user who no longer has to worry about being in the correct gear ratio.

It is known from document DE 10 2019 123 288 A1 an actuator for changing the transmission ratios of a vehicle, in particular a bicycle. The actuator described in this document has the disadvantage of being bulky due to a complex mechanism between the electric motor and the output element of the actuator coupled with the transmission.

The object of the present invention is to improve current solutions, in particular by proposing a compact, lightweight actuator with reliable actuation kinematics supporting the forces.

More particularly, the invention relates to an actuator for actuating at least one movable member of a vehicle transmission, said actuator comprises a housing in which are housed an electric motor having a shaft on which is mounted a first pinion, a toothed wheel having a toothing meshing with the pinion and a torque output element adapted to be coupled with the transmission, the housing comprises a pin projecting in the direction of the toothed wheel and of the first pinion.

Thus, the actuator according to the invention is particularly compact while integrating a means of taking up the forces between the first pinion and the toothed wheel, which prevents tilting of the toothed wheel.

According to the invention, the first pinion and the teeth of the toothed wheel form a face gear called “face gear ” . This type of gear has the particularity of being simple to implement because it requires precise positioning along two axes and allows more robust operation.

According to a characteristic of the invention, the pin is cylindrical.

According to a feature of the invention, a clearance of between 0.1mm and 1mm is defined between the pin and the toothed wheel.

According to one characteristic of the invention, the toothed wheel comprises a first disc-shaped part with an internal face facing the housing and an external face, said toothing is formed at the periphery of the external face, the toothed wheel further comprises a second barrel-shaped part extending from the outer face of the first part and on which the torque output element is located, said first part and second part are in one piece.

According to the invention, the toothed wheel further comprises a worm mechanism meshing with a second pinion mounted on a shaft, said shaft comprising a magnetic target facing a sensor housed in the housing.

According to a characteristic of the invention, the worm mechanism is located on the second shaft-shaped part of the toothed wheel or on the first disc-shaped part on the external face of the toothed wheel.

According to the invention, the target is fixed to a first end of the shaft by means of a target support, said shaft being guided in rotation by a first bearing surrounding the target support and by a second bearing surrounding the shaft at a second end of the shaft.

According to another characteristic of the invention, the second pinion is located substantially in the middle of the shaft between the first and the second bearing.

According to one characteristic of the invention, the electric motor, the shaft via its bearings and the sensor are held in the housing by fixing means made in the form of clips.

Other characteristics and advantages of the invention will become apparent on reading the following examples of detailed embodiments, with reference to the appended figures:

there shows a perspective view of the actuator mechanism according to a first embodiment;

there shows a sectional view of the shaft of the actuator on which the target and the second pinion are mounted;

there represents the mechanism of integrated in a housing;

there shows a top view of the actuator of the , in particular focused on fixing the shaft in the housing;

there and the represent a cross-sectional view of the means for fixing the electric motor;

there shows a sectional view of the actuator along an axis passing through the rotation shaft of the toothed wheel and the shaft of the electric motor;

there shows a perspective view of the actuator mechanism according to a second embodiment.

In the rest of the description, identical elements or identical functions bear the same reference sign. For the purpose of conciseness of this description, these elements are not described in detail in each embodiment and only the differences between the alternative embodiments are described in detail.

On the , an X, Y, Z marker has been illustrated. The X direction or axis corresponds to a longitudinal direction. The transverse direction or axis Y is defined as being perpendicular to the longitudinal direction X. More specifically, the longitudinal and transverse directions X and Y can for example belong substantially to a substantially horizontal plane. The Z direction or axis corresponds to a vertical direction.

There represents the internal mechanism of the actuator 1 according to a first mode of the invention. The mechanism is formed by a direct current electric motor 2 having a shaft 21 on which is mounted a first pinion 22. The first pinion 22 can be made of plastic or metal. For reasons of compactness, the electric motor 2 is a flat motor, that is to say that the carcass of the electric motor 2 has two flats 23 which reduce its vertical size. Shaft 21 extends along axis X.

The first pinion 22 which is a spur gear cooperates with a toothed wheel 3. This toothed wheel has a toothing 31 in order to form a face gear with the first pinion 22. The toothed wheel 3 comprises a first part in the form of a disc with a side internal and an external face. The first disc-shaped part extends substantially along a plane parallel to the plane defined by the longitudinal and transverse directions X and Y. The internal face is defined as being the face facing the housing 6 (not visible on the ). The outer face is defined as the face opposite the inner face. The toothing 31 is formed at the periphery of the outer face of the toothed wheel 3. The toothed wheel 3 further comprises a second barrel-shaped part 32 which extends vertically from the outer face of the first part and on which finds the torque output element 33. The second barrel-shaped part 32 extends vertically along the Z axis, that is to say that the barrel 32 extends perpendicularly with respect to the first barrel-shaped part. disk shape.

The torque output element 33 is here a connection means in the form of a female star fitting into which a transmission member is fitted, for example a transmission shaft on which a shuttle moves linearly making it possible to select a transmission report. In a variant not shown, the torque output element 33 can be a male star tip. Any other means making it possible to transmit a torque can be envisaged to produce the torque output element 33.

The first part and the second part of the toothed wheel 3 are in one piece, that is to say that the toothed wheel 3 is made of a single material, for example plastic, more precisely polyoxymethylene. The rotational torque supplied by the electric motor thus passes through the first pinion 22, then through the toothed wheel 3 and is transmitted to the movable member of the transmission (not shown) via the torque output element 33.

In order to know precisely the position of the movable member of the transmission and thus the gear engaged, it is necessary to know the angular position of the toothed wheel 3. For reasons of vertical compactness of the actuator 1, it is impossible to position a magnet and a sensor along the Z axis, it is then necessary to deport the magnet and the sensor in another direction which does not impact the compactness of the actuator along the Z axis.

To do this, the toothed wheel 3 comprises a worm mechanism 4 which meshes with a second pinion 41 mounted on a shaft 40. The worm mechanism is a thread. In the embodiment of the , the worm mechanism 4 is located on the second barrel-shaped part 32 of the toothed wheel 3. The worm mechanism 4 is located on the barrel 32 near the first part of the toothed wheel 3. The reduction ratio of the worm screw mechanism 4 is determined so that for a determined number of revolutions of the toothed wheel 3, the shaft 40 performs only one revolution.

In the present case, the reduction ratio is such that the toothed wheel 3 performs eleven revolutions, i.e. 3960°, while the shaft 40 performs one revolution, i.e. 360°. The eleven revolutions of the toothed wheel 3 correspond to the displacement of the movable member of the transmission between its two extreme positions making it possible to cover all the gear changes of the transmission. The number of teeth of the second pinion 41 is identical to the number of turns necessary for the toothed wheel 3 to move the movable member of the transmission between its two extreme positions plus a guard of one tooth which corresponds to one additional turn. In this case, the pinion 41 has eleven teeth which corresponds to the eleven revolutions of the toothed wheel 3.

The shaft 40 will now be described with reference to Figures 1 and 2. The shaft 40 extends along the Y axis and consists of a metal shaft on which is mounted the second pinion 41 which cooperates with the mechanism endless screw 4 of the toothed wheel 3. Alternatively, the shaft 40 may be plastic. The second pinion 41 can be plastic or metal. A target 44 facing a sensor 50 is fixed to a first end of the shaft 40 via a target support 45.

The target 44 is here a magnetic target, that is to say that the target 44 is a permanent magnet. The target 44 thus generates a magnetic field intended to influence the magnetic sensor 50 which is in particular a Hall effect probe. It is thus possible, depending on the signal emitted by the sensor 50, to determine the exact position of the mobile member of the transmission between its two extreme positions.

The target 44 is cylindrical in shape and is centered on the Y axis. The target 44 is mounted and held in the target support 45 by a fixing means, for example by gluing or by overmoulding. The target support 45 is a substantially cylindrical part made of plastic, in particular polyoxymethylene, and is connected to the shaft 40. For example, the target support 45 is fitted and glued onto the shaft 40. As a variant, the 45 target and shaft are one piece. The internal surface of the target support 45 receives the target 44 and the external surface of the target support 45 receives a first bearing 42 for guiding the shaft 40.

The shaft 40 is guided in rotation by the first bearing 42 surrounding the target support 45 and by a second bearing 43 surrounding the shaft 40 at a second end of the shaft 40. The bearings 42, 43 are bronze bearings or brass. As a variant, the bearings 42, 43 can be made of plastic, for example polyetheretherketone. The bearings 42, 43 have different diameters. The first bearing 42 surrounding the target support 45 has a larger diameter than the second bearing 43. The second pinion 41 is located substantially in the middle of the shaft 40 between the first bearing 42 and the second bearing 43.

There shows the mechanism of integrated in a casing 6. The casing 6 is suitable for being fixed to the transmission of the vehicle in particular by means of fixing means, for example screws, passing through several openings 61 made at the periphery of the casing 6. A seal is placed in a peripheral groove 62 of the housing 6 in order to provide a seal between the housing 6 of the actuator 1 and the transmission. The seal is for example made of EPDM or FKM or silicone. The housing is for example made of plastic, in particular of plastic reinforced with fiberglass.

The housing 6 houses the electric motor 2, the toothed wheel 3, the shaft 40, and the sensor 50 in its internal volume. The box 6 further comprises an electrical connector 60 in order to electrically connect the electric motor 2 and the sensor 50 to an electrical source. The electrical connector 60 also makes it possible to recover the signal emitted by the sensor 50. The electrical connector 60 is connected to the electric motor 2 and to the sensor 50 via conductive tracks molded into the casing 6. The connector 60 is waterproof and incorporates a joint.

The electric motor 2, the shaft 40 and the sensor 50 are held in the casing 6 by fixing means made in the form of clips. Figures 3, 5 and 6 illustrate these fastening means. There shows the rear part of the electric motor 2 fixed to the casing 6 by two clips 671 formed by two protrusions 67 of the casing 6 and by a stop 672. The stop 672 is used to position it on the casing 6 and the two clips 671 are used to hold in position of the electric motor 2 in the housing 6.

The same principle is used to attach the front part of the electric motor as illustrated in the . The front part of the electric motor 2 is fixed to the casing 6 by two clips 661 formed by two protuberances 66 of the casing 6 and by a stop 662. The stop 662 is used to position it on the casing 6 and the two clips 661 serve to hold in position of the electric motor 2 in the housing 6.

Referring to Figures 3 and 4, the shaft 40 is also fixed to the housing 6 by fixing means made in the form of clips. The first bearing 42 is fixed to the casing 6 by two clips 64 formed by two protrusions of the casing 6. The second bearing 43 is fixed to the casing 6 by three clips 63 formed by three protrusions of the casing 6. In order to block the translation of the shaft 40 in direction Y, a pin 68 is formed by a protuberance of housing 6. As an alternative to pin 68, blocking of shaft 40 in direction Y can be achieved by a protrusion of one of clips 63 in direction of shaft 40.

The sensor 50 is also fixed to the casing 6 by fixing means made in the form of clips, the sensor 50 is in particular positioned between two walls 69. The electrical connections of the sensor 50 are connected to the overmolded conductive tracks of the casing 6 by pins connection 65.

There shows the rotational guidance of the toothed wheel 3 in the housing 6 by means of a shaft 7. The shaft 7 is inserted into a guide shaft 71 of the housing 6. The shaft 7 can be glued into the shaft 71 or be molded into shaft 71. The toothed wheel 3 comes into abutment against one end 72 of this guide shaft 71 in order to be blocked in translation along the axis Z. During operation of the actuator 1, it it is possible that the toothed wheel 3 swivels due to the pressure angle of the face gear between the first pinion 22 and the toothing 31 which tends to cause the toothed wheel to tilt in a direction according to the arrow F. To counter this inconvenience, a pin 80 is arranged in the housing 6 opposite the internal face of the first part of the toothed wheel 3 at the level of the toothing 31. The pin 80 protrudes in the direction of the toothed wheel 3 and of the first pinion 22 In other words, the pin 80 protrudes in line with the first pinion 22 from the housing 6 and the toothed wheel 3 lies between the pin 80 and the first pinion in the direction of the extension of the pin 80. The pin 80 extends in a direction parallel to the direction Z. The pin 80 is cylindrical. A clearance of between 0.1mm and 1mm is defined between pin 80 and toothed wheel 3.

There illustrates an actuator 1' according to a second embodiment of the invention. Unlike the first embodiment, the worm mechanism 4' of the actuator 1' is located on the first disc-shaped part on the outer face of the toothed wheel 3'. The endless screw mechanism 4' thus forms a cam track in the form of a spiral. The operation is identical to the first embodiment, that is to say that the reduction ratio of the worm screw mechanism 4' is determined so that for a determined number of revolutions of the toothed wheel 3', the shaft 40' performs only one turn.

Although the invention has been described in connection with several particular embodiments, it is obvious that it is in no way limited thereto and that it includes all the technical equivalents of the means described as well as their combinations if these fall within the scope of the invention.

In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims (10)

Actuator (1, 1') for actuating at least one moving member of a vehicle transmission, said actuator (1, 1') comprises a casing (6) in which an electric motor (2) is housed a shaft (21) on which is mounted a first pinion (22, 22'), a toothed wheel (3, 3') having a toothing (31, 31') meshing with the pinion (22, 22') and an element torque output (33) able to be coupled with the transmission, characterized in that the housing (6) comprises a pin (80) projecting in the direction of the toothed wheel (3, 3') and of the first pinion (22 , 22'). Actuator according to Claim 1, characterized in that the first pinion (22, 22') and the toothing (31, 31') of the toothed wheel (3, 3') form a face gear. Actuator according to Claim 1 or 2, characterized in that the pin (80) is cylindrical. Actuator according to one of the preceding claims, characterized in that a play of between 0.1mm and 1mm is defined between the pin (80) and the toothed wheel (3, 3'). Actuator according to one of the preceding claims, characterized in that the toothed wheel (3, 3') comprises a first disc-shaped part with an internal face facing the casing (6) and an external face, said toothing (31 , 31') is formed at the periphery of the outer face, the toothed wheel (3, 3') further comprises a second barrel-shaped part (32) extending from the outer face of the first part and on which is the torque output element (33), said first part and second part are integral. Actuator according to one of the preceding claims, characterized in that the toothed wheel (3, 3') further comprises a worm screw mechanism (4, 4') meshing with a second pinion (41, 41') mounted on a shaft (40), said shaft (40) comprising a magnetic target (44) facing a sensor (50) housed in the housing (6). Actuator according to Claims 5 and 6, characterized in that the worm mechanism (4') is located on the second barrel-shaped part (32) of the toothed wheel (3) or on the first barrel-shaped part disk on the external face of the toothed wheel (3). Actuator according to Claim 6 or 7, characterized in that the target (44) is fixed to a first end of the shaft (40) by means of a target support (45), the said shaft (40) being guided in rotation by a first bearing (42) surrounding the target support (45) and by a second bearing (43) surrounding the shaft (40) at a second end of the shaft (40). Actuator according to Claim 8, characterized in that the second pinion (41) is located substantially in the middle of the shaft (40) between the first and the second bearing (42, 43). Actuator according to Claim 6, characterized in that the electric motor (2), the shaft (40) and the sensor (50) are held in the casing (6) by fixing means (66, 67, 63, 64 ) made in the form of clips.